Abstract: A power take-off system for a gas turbine engine includes a starter coupled to a first spool using a first shaft, and a generator coupled to the second spool using a second shaft, the first shaft is circumferentially offset by the second shaft by an angle ?. A method of assembling a gas turbine engine assembly that includes the power take-off system, and a gas turbine engine assembly including the power take-off system are also described.

Abstract: A turbofan engine assembly is provided. The turbofan engine assembly includes a core gas turbine engine, a core cowl which circumscribes the core gas turbine engine, a nacelle positioned radially outward from the core cowl, a fan nozzle duct defined between the core cowl and the nacelle, and an inner core cowl baffle assembly positioned within the fan nozzle duct. The inner core cowl baffle assembly includes a first core cowl baffle coupled to a portion of the core cowl within the fan nozzle duct, a second core cowl baffle coupled to a portion of the core cowl and positioned a distance radially inward from the first core cowl baffle, and an actuator assembly configured to vary the throat area of the fan nozzle duct by selectively repositioning the second core cowl baffle with respect to the first core cowl baffle. A method for operating the turbofan engine assembly is also provided.

Abstract: A gas turbine engine includes a compressor, combustor, and high pressure turbine operatively joined together. The turbine includes a row of nozzle vanes followed by a row of rotor blades. The vanes and blades have corresponding forward and aft internal cooling channels. First, second, third, and fourth bleed circuits are joined in flow communication with different stages of the compressor for bleeding pressurized air therefrom at different pressures to provide coolant to the forward and aft channels of the turbine vanes and blades.

Abstract: A method for operating a turbofan engine assembly is provided. The turbofan engine assembly includes a core cowl which circumscribes the core gas turbine engine, a nacelle positioned radially outward from the core cowl, a fan nozzle duct having an area defined between the core cowl and a portion of the nacelle, a first cowl and a second cowl that define a portion of the nacelle wherein the second cowl is repositionable with respect to the first cowl, and a thrust reverser assembly wherein the second cowl surrounds the thrust reverser assembly. The method includes varying an operating speed of the fan assembly from a first operating speed to a second operating speed. The method further includes selectively positioning the second cowl between a first operational position and a second operational position to vary the area of the fan nozzle duct to facilitate improving engine efficiency at the second operating speed.

Abstract: An inner core cowl baffle assembly for a turbofan engine assembly is provided. The engine assembly includes a core gas turbine engine, a core cowl which circumscribes the core gas turbine engine, a nacelle positioned radially outward from the core cowl, and a fan nozzle duct defined between the core cowl and the nacelle. The inner core cowl baffle assembly includes an inner core cowl baffle, and an actuator assembly configured to vary the throat area of the fan nozzle duct by selectively repositioning the inner core cowl baffle with respect to the core cowl.

Abstract: A gas turbine engine includes a compressor, combustor, and high pressure turbine operatively joined together. The turbine includes a nozzle followed by a row of rotor blades. A first bleed circuit is joined in flow communication between the last stage of the compressor and a forward cooling channel in vanes of the nozzle for feeding first cooling holes therein with pressurized primary air at a first pressure. A second bleed circuit is joined in flow communication between an intermediate stage of the compressor and aft cooling channels in the nozzle vanes to feed second cooling holes with pressurized secondary air at a second pressure less than the first pressure.

Abstract: A gas turbine engine includes a compressor, combustor, and high pressure turbine operatively joined together. A first interstage bleed circuit is joined in flow communication between a first preultimate stage of the compressor and hollow blades in the turbine to provide thereto pressurized primary air. A second interstage bleed circuit is joined in flow communication between a second preultimate stage of the compressor and the turbine blades to provide thereto pressurized secondary air at a lower pressure than the primary air.

Abstract: A gas turbine engine includes a compressor, combustor, and high pressure (HP) turbine operatively joined together. An interstage cooling circuit is joined in flow communication from an intermediate stage of the compressor to a forward face of an HP disk supporting a row of turbine blades for channeling interstage bleed cooling air thereto.

Abstract: A turbofan engine assembly includes a core gas turbine engine including a high-pressure compressor, a combustor, and a high-pressure turbine, a low-pressure turbine coupled to said core gas turbine engine, a counter-rotating booster compressor comprising a first rotor section configured to rotate in a first direction and a second rotor section configured to rotate in an opposite second direction, and a gearbox comprising an input and an output, said gearbox output coupled to at least one of said first and second rotor sections, said gearbox input coupled to said low-pressure turbine. A method of assembling the turbofan engine assembly described herein is also provided.

Abstract: A method of assembling a gas turbine assembly includes providing a core gas turbine engine including a high-pressure compressor, a combustor, and a turbine, coupling a low-pressure turbine to the core gas turbine engine, coupling a booster compressor to a gearbox, and coupling the gearbox to the low-pressure turbine such that the booster compressor is driven by the low-pressure turbine.

Abstract: A turbofan engine assembly includes a core gas turbine engine including a high-pressure compressor, a combustor, and a high-pressure turbine, a booster compressor coupled upstream from the core gas turbine engine, an intermediate-pressure turbine coupled to the booster compressor, the intermediate-pressure turbine disposed downstream from the core gas turbine engine, a counter-rotating fan assembly disposed upstream from the booster compressor, the counter-rotating fan assembly comprising a first fan configured to rotate in a first direction and a second fan configured to rotate in an opposite second direction, and an intermediate-pressure turbine disposed downstream from the core gas turbine engine, wherein the intermediate-pressure turbine drives the booster compressor and the second fan assembly. A method of assembling the above turbofan engine assembly is also described herein.

Abstract: A method for assembling a gas turbine engine includes coupling a low-pressure turbine to a core turbine engine, coupling a counter-rotating fan assembly including a forward fan assembly and an axially aft fan assembly to the low-pressure turbine such that the forward fan assembly rotates in a first direction and the aft fan assembly rotates in an opposite second direction, and coupling a booster compressor directly to the low-pressure turbine such that the booster compressor rotates in the first direction.

Abstract: A turbofan engine assembly includes a core gas turbine engine including a high-pressure compressor, a combustor, and a high-pressure turbine, a booster compressor coupled upstream from the core gas turbine engine, an intermediate-pressure turbine coupled to the booster compressor, the intermediate-pressure turbine disposed downstream from the core gas turbine engine, a first fan assembly coupled to a low-pressure turbine, a second fan assembly disposed downstream from the first fan assembly, and a gearbox coupled between the second fan assembly and the low-pressure turbine. A method of assembling the above turbofan engine assembly is also described herein.

Abstract: A turbofan engine assembly includes a core gas turbine engine including a high-pressure compressor, a combustor, and a high-pressure turbine, a booster compressor coupled upstream from the core gas turbine engine, an intermediate-pressure turbine coupled to the booster compressor, the intermediate-pressure turbine disposed downstream from the core gas turbine engine, a counter-rotating fan assembly disposed upstream from the booster compressor, the counter-rotating fan assembly comprising a first fan configured to rotate in a first direction and a second fan configured to rotate in an opposite second direction, and a low-pressure turbine disposed downstream from the intermediate-pressure turbine, the low-pressure turbine configured to drive the counter-rotating fan assembly. A method of assembling the above turbofan engine assembly is also described herein.

Abstract: A method facilitates assembling a gas turbine engine including a compressor and a rotor assembly coupled in axial flow communication downstream from the compressor. The method comprises coupling a bypass system in flow communication with the compressor to channel a portion of flow discharged from the compressor towards the rotor assembly is channeled through the bypass system, and coupling a downstream end of the bypass system within the gas turbine engine such that the flow entering the bypass system flows past the rotor assembly and is discharged downstream from the rotor assembly.

Abstract: A method for assembling a gas turbine engine assembly includes coupling a fan assembly to a core gas turbine engine such that the fan assembly is upstream from the core gas turbine engine, coupling a low-pressure turbine downstream from the core gas turbine engine such, wherein the low-pressure turbine includes a disk and a plurality of splines formed in the disk, providing a shaft that includes a first end and a second end that includes a plurality of splines, coupling the shaft first end to the fan assembly, and coupling the shaft second end to the low-pressure turbine such that the shaft splines mesh with the disk splines such that torque is transmitted from the low-pressure turbine to the fan assembly via the shaft during engine operation.

Abstract: A method for assembling a gas turbine engine including a core gas turbine engine, a low-pressure turbine, a starter, and a generator is provided. The method includes coupling a starter to the core gas turbine engine, and coupling a generator to the low-pressure turbine.

Abstract: A method for fabricating a gas turbine engine outlet guide vane includes fabricating an airfoil that includes a leading edge portion and a trailing edge portion each fabricated from a first material, and installing a filler portion between the leading and trailing edge portions, the filler portion is fabricated from a second material that is lighter than the first material.

Abstract: A method for assembling a gas turbine engine assembly includes coupling a fan assembly to a core gas turbine engine such that the fan assembly is upstream from the core gas turbine engine, coupling a fan assembly to a core gas turbine engine such that the fan assembly is upstream from the core gas turbine engine, wherein the core gas turbine engine includes a high-pressure turbine, coupling a low-pressure turbine downstream from the core gas turbine engine such, wherein the low-pressure turbine includes a disk and a plurality of splines formed in the disk, providing a shaft that includes a first end and a second end that includes a plurality of splines, coupling the shaft between the low-pressure turbine and the fan assembly, and coupling a differential bearing between the shaft and the high-pressure turbine such that the shaft provides rotational support for the high-pressure turbine.

Abstract: A method for assembling a gas turbine engine that includes providing a low-pressure turbine inner rotor that includes a first plurality of rows of turbine blades configured to rotate in a first rotational direction, providing a low-pressure turbine outer rotor that includes a second plurality of rows of turbine blades configured to rotate in a rotational direction that is opposite the first rotational direction, and coupling a support structure between the outer rotor and a turbine mid-frame such that the support structure supports a forward end of the outer rotor, and wherein the support structure includes a first portion that has a first coefficient of thermal expansion and a second portion that has a second coefficient of thermal expansion that is different than the first coefficient of thermal expansion.